Urban metabolism etymologically comes from the term metabolism which derives from the Greek μεταβολή, change, e -ism[1]​ and from the term urban which derives from the Latin urbānus.[2]​ It is the exchange of matter "Matter (physical)"), energy and information that is established between the urban settlement and its natural environment or geographical context. This formulation of the concept of urban metabolism was given by the Ministry of Public Works and Urban Planning in 1990, after the analysis carried out on the urban environment.

The biosphere, like any open system, exchanges substances and dissipates energy, and the reproductive and transformation capacity of the subsystem depends on this exchange, which is why the system is as important as the environment. This system is made up of subsystems, and man, his machines and his communication networks are part of its energy and information diagrams.

Urban metabolism determines our demands for raw materials and the impact that their use has on the biosphere, helping us understand the relationships between these materials and social processes.[3]​[4]​

Urban areas have a high concentration of energy per unit area compared to a crop field or a natural ecosystem. The magnitudes of the flows generated in cities, as we all notice today, are causing imbalances in nature, perhaps the most prominent of which are environmental.[5]​.

A term of recent creation but of rigorous depth for multiple investigations encouraged by the problems and paradigm of urban sustainability in our cities.

Sustainability is closely related to the pressure we exert on the natural environment that surrounds us, and to slow down this pressure, new indicators of urban metabolism must be identified, as well as work on a new urbanism that efficiently manages these metabolic flows and is capable of transforming a city with a linear metabolism into cities with a circular metabolism that imitate the functioning of nature, and everything can be recycled and reused.[6][7]​.

"Cities are more than just structures of stone and concrete; they are also immense processors of food, fuel and all the raw materials that nourish civilization. They are enormous organisms with a complex metabolism unprecedented in nature; they are artificial in nature, since they concentrate (in a small area) quantities of food, water and materials that are much greater than what nature is capable of providing; consequently, the consumption of these resources generates enormous amounts of garbage and wastewater, and in the same way that nature does not It cannot concentrate all the resources necessary to make urban life sustainable, nor can it disperse the waste produced” (Yunén, 1997).